Method of preventing mine explosions.



981,170. Patnted .10, 1911,

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JOHN W. COLEMAN, OF MAYBEUEY, WEST VIRGINIA, ASSIGNOR OF ONE-HALF TO ANDREW J. DALTON, OF POWHATAN, WEST VIRGINIA.

METHOD OF PREVENTING MINE EXPLOSIONS.

Application filed January 25, 1910.

To all whom it may concern:

Be it known that 1, JOHN W. COLEMAN, a citizen of the United States, residing at Maybeury, in the county of McDowell and State of est Virginia, have invented certain new and useful Improvements in Methods for Preventing Mine Explosions, of which the following is a specification, reference being had to the accompanying drawings.

This invention relates to a new and novel method for preventing mine explosions which resides primarily in the introduction into the passages of the mine of a continuously circulating draft of heated air, and the injection into said air current of moisture in such quantity in proportion to the degree of heat that the same will be held in suspension and carried into the various mine passages and precipitated to the floor there of whereby the particles of dust in the air will be allayed and the possibility of an explosion due to the heat which is generated by the gases of the mine thus obviated.

In the drawing I have illustrated a diagrammatic view of the interior of a mine showing the parallel longitudinal inlet and outlet passages and the rooms or chambers, and one of the means adapted for the ap plication of my improved method.

As set forth in my pending application for patent filed December 11, 1909, Serial No. 532,664, one of the most prevalent causes of mine explosions is the explosion of dust particles with which the air of the mine becomes impregnated. The above mentioned application recites a method which consists in introducing heated air into the mine, the moisture thereof being precipitated by the contact of the air current with the comparatively cold walls of the mine whereby the dust particles are allaycd and the explosion prevented.

While the above method is effective in many instances, it has been demonstrated that when the air is very dry in extremely cold weather, the moisture contained therein will be insufiicient to insure the accomplishment of the purpose for which the invention is devised. I have therefore found that the introduction of a jet of vapor into the current of heated air as it passes into the mine will effectually overcome the deficiency and insure a sufiicient precipitation Specification of Letters Patent.

Patented J an. 10, 1911.

Serial No. 540,033.

of moisture to preclude the possibility of the retention of any dust particles which might be exploded by the accumulation of the mine gases. It has been determined by experiment that a current of air at 32 Fahrenheit can carry in suspension a two hundred and thirty-sixth part of its own weight, while air at 72 Fahrenheit is capable of carrying in suspension a fifty-ninth part of its own weight. Therefore in carrying out my invention, I preferably heat the air before introducing the same into the mine to the latter degree and then introduce into the air current moisture in the form of a steam jet in such quantity as not to exceed the above named proportion whereby such moisture will be carried into and through the various passages of the mine by the air current and gradually precipitate such moisture during its circulation.

In the drawing 5 represents the inlet passage of a mine in the entrance of which a radiator or other suitable heating element 6 is arranged. At its rear end this passage communicates with the parallel longitudinal passage 7 in the outer end of which a rotary fan 8 is arranged whereby the vitiated or impure air is exhausted from the mine. A plurality of rooms or chambers 9 communicate with the outlet passage 7 as shown at 10, and these rooms or chambers are connected to each other by the communicating passages 11. Supported in the mouth of the entrance passage of the mine in any preferred manner as by means of the brackets 12, a flexible steam conducting hose 18 is arranged. This hose is connected to the sourceof steam supply and is provided upon its extremity with a nozzle 14 which is disposed in advance of the radiator 6 and is adapted to discharge the steam jet at a comparatively high velocity, although this is not essential to the object of the invention.

As stated in the above mentioned appli. cation, the majority of mine explosions occur in winter when the air is very dry and contains but little moisture. At such times the air of the mine is thickly laden with the dust particles and the danger of explosion is imminent while in summer when the air is warmer and contains a greater per cent. of moisture such explosions are less frequent. Therefore in carrying out my improved method, the air is introduced into the mine i such exhaustion of the air being facilitated in any preferred manner and the same is heated as it passes from the radiator 6 to a temperature of 72 or more. At this temperature, the steam jet is injected into the air current and this added moisture is carried into the mine as the air circulates through the passages and chambers therein. The walls of the mine being comparatively cold, the vapor willbe condensed as the air impinges upon the surfaces of the walls and Will be precipitated in the form of water. This water assimilates the dust particles in its fall and thus prevents the accumulation of dust particles in the air of the mine. The heated air circulates through the mine channels or passages as indicated by the arrows in the drawing and is finally exhausted from the outer open end of the outlet passage 7 by the fan 8.- In this manner the mine is rendered absolutely proof from explosions due to the accumulation of dust particles in the air.

ing air out of the mine at another point, and

hence maintaining a circulation of air; heating the air near the point of intake to the temperature of about 72 F and injecting into the current of air at the point where the same is heated, a jet of steam in the same general direction as the said air current, to supply suflicient moisture to the air to cause the precipitation of the dust particles therein.

In testimony whereof I hereunto aflix my signature in the presence of two witnesses.

JOHN V. COLEMAN.

Vitnesses A. J. DALTON, J. W. BINGHAM. 

